* Fix MultiCompiler watch mode stats output
Previously, stats would contain stale configuration child stats. This is very confusing, since it looks as if some things are emitted when they shouldn't be.
Add support for making assertions to stats in watch tests.
* Fix test hanging on Windows/Linux
Parallel watchpack's (happens when MultiCompiler is in use) do not emit events in watch tests, unless some timeout is added.
This does not seem to be an issue on macOS.
* Correctly close watcher in watch tests
This fixes macOS build, where changes keep being triggered